Design and fabrication of an integrated three-dimensional tactile sensor for space robotic applications

An integrated three-dimensional tactile sensor with robust structure and soft contact surface suitable for space robotic applications was developed. The sensor has a maximum force range of 50 N in the vertical direction and /spl plusmn/10 N in the x-y horizontal directions. The sensitivity of the sensor cells in the vertical direction is 13 m V/V and in the x and y horizontal directions are both 2.3 mV/N. The tactile sensor includes 4/spl times/8 sensing cells each exhibiting an independent linear response to the three components of forces. Post bulk-micromachining was performed on foundry fabricated CMOS chips to produce the sensor cells. With neural network training, the tactile sensor produced reliable 3-axes force measurements and repeatable response on tactile images. Design analysis, fabrication procedures, and experimental results are presented in this paper.